Of 2 Minds: How Fast and Slow Thinking Shape Perception and Choice [Excerpt]

In psychologist Daniel Kahneman's recent book, he reveals the dual systems of your brain, their pitfalls and their power















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PLOT SYNOPSIS

The interaction of the two systems is a recurrent theme of the book, and a brief synopsis of the plot is in order. In the story I will tell, Systems 1 and 2 are both active whenever we are awake. System 1 runs automatically and System 2 is normally in a comfortable low-effort mode, in which only a fraction of its capacity is engaged. System 1 continuously generates suggestions for System 2: impressions, intuitions, intentions, and feelings. If endorsed by System 2, impressions and intuitions turn into beliefs, and impulses turn into voluntary actions. When all goes smoothly, which is most of the time, System 2 adopts the suggestions of System 1 with little or no modification. You generally believe your impressions and act on your desires, and that is fine—usually.

When System 1 runs into difficulty, it calls on System 2 to support more detailed and specific processing that may solve the problem of the moment. System 2 is mobilized when a question arises for which System 1 does not offer an answer, as probably happened to you when you encountered the multiplication problem 17 × 24. You can also feel a surge of conscious attention whenever you are surprised. System 2 is activated when an event is detected that violates the model of the world that System 1 maintains. In that world, lamps do not jump, cats do not bark, and gorillas do not cross basketball courts. The gorilla experiment demonstrates that some attention is needed for the surprising stimulus to be detected. Surprise then activates and orients your attention: you will stare, and you will search your memory for a story that makes sense of the surprising event. System 2 is also credited with the continuous monitoring of your own behavior—the control that keeps you polite when you are angry, and alert when you are driving at night. System 2 is mobilized to increased effort when it detects an error about to be made. Remember a time when you almost blurted out an offensive remark and note how hard you worked to restore control. In summary, most of what you (your System 2) think and do originates in your System 1, but System 2 takes over when things get difficult, and it normally has the last word.

The division of labor between System 1 and System 2 is highly efficient: it minimizes effort and optimizes performance. The arrangement works well most of the time because System 1 is generally very good at what it does: its models of familiar situations are accurate, its short-term predictions are usually accurate as well, and its initial reactions to challenges are swift and generally appropriate. System 1 has biases, however, systematic errors that it is prone to make in specified circumstances. As we shall see, it sometimes answers easier questions than the one it was asked, and it has little understanding of logic and statistics. One further limitation of System 1 is that it cannot be turned off. If you are shown a word on the screen in a language you know, you will read it—unless your attention is totally focused elsewhere.
 

CONFLICT

Figure 2 is a variant of a classic experiment that produces a conflict between the two systems. You should try the exercise before reading on.

You were almost certainly successful in saying the correct words in both tasks, and you surely discovered that some parts of each task were much easier than others. When you identified upper- and lowercase, the left-hand column was easy and the right-hand column caused you to slow down and perhaps to stammer or stumble. When you named the position of words, the left-hand column was difficult and the right-hand column was much easier.

These tasks engage System 2, because saying “upper/lower” or “right/ left” is not what you routinely do when looking down a column of words. One of the things you did to set yourself for the task was to program your memory so that the relevant words (upper and lower for the first task) were “on the tip of your tongue.” The prioritizing of the chosen words is effective and the mild temptation to read other words was fairly easy to resist when you went through the first column. But the second column was different, because it contained words for which you were set, and you could not ignore them. You were mostly able to respond correctly, but overcoming the competing response was a strain, and it slowed you down. You experienced a conflict between a task that you intended to carry out and an automatic response that interfered with it.



9 Comments

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  1. 1. Asteroid Miner 08:43 AM 6/16/12

    There is a problem with the figures. I see only a little blue square.

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  2. 2. kered 09:30 AM 6/16/12

    Excellent article, but would be MUCH better if we could see the pictures. EDITOR... please reformat so we can read easily... Using system 1 for the pics!!!!!!

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  3. 3. mike_midwest 02:33 PM 6/17/12

    17x24 = 17x3x8 = 51x8 = (50+1)x8 = 400+8 = 408.

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  4. 4. HdeJong 04:30 PM 6/17/12

    (16+1)*25-17 = 425-17 = 408

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  5. 5. kered 07:27 PM 6/17/12

    hard math... try this way
    17*24= 20*24-3*24 = 480-72=408
    I am out of practice, took me ~~30 mins to figure this out... Whatever way, System 2, as System 1 cannot do these!!! Great article

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  6. 6. hugoal 06:31 AM 6/18/12

    Try this way:
    17*24=10*24+(10-3)*24=240+(240-72)=240+168=408
    or this one that's even easier:
    17*24=(10+10/2+2)*24=10*24+(10*24)/2+2*24=240+240/2+48=240+120+48=408
    Great article.

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  7. 7. euroflycars 04:15 PM 6/18/12

    Try that way:

    17*2=34 --> 17*20=340
    17*4=68

    340+68=408

    It's opportunistic, but that's why clever calculators will do it almost intuitively with their system 1.

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  8. 8. GeorgeOckel 05:24 PM 6/20/12

    Article seems interesting but without pictures loses appeal

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  9. 9. craigc0 03:48 PM 8/7/12

    needs the pictures. This has been noted many times, but no response.

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